Add practical reproducer tests to verify/trigger the consumer stalling bug:
1. TestConsumerStallingPattern (INTEGRATION REPRODUCER)
- Documents exact stalling pattern with setup instructions
- Verifies consumer doesn't stall before consuming all messages
- Requires running load test infrastructure
2. TestOffsetPlusOneCalculation (UNIT REPRODUCER)
- Validates offset arithmetic (committed + 1 = next fetch)
- Tests the exact stalling point (offset 163 → 164)
- Can run standalone without broker
3. TestEmptyFetchShouldNotStopConsumer (LOGIC REPRODUCER)
- Verifies consumer doesn't give up on empty fetch
- Documents correct vs incorrect behavior
- Isolates the core logic error
These tests serve as both:
- REPRODUCERS to trigger the bug and verify fixes
- DOCUMENTATION of the exact issue with setup instructions
- VALIDATION that the fix is complete
To run:
go test -v -run TestOffsetPlusOneCalculation ./internal/consumer # Passes - unit test
go test -v -run TestConsumerStallingPattern ./internal/consumer # Requires setup - integration
If consumer stalling bug is present, integration test will hang or timeout.
If bugs are fixed, all tests pass.